1. Field of the Invention
The present invention relates to state nodes and, more particularly, to a method of identifying state nodes at the transistor level in a sequential digital circuit.
2. Description of the Related Art
A state node in a sequential digital circuit represents a memory element. It has two stable states (logic 1 and logic 0), and can retain its value or memory until some other data is written on it. For example, the outputs of all of the flipflops in a sequential digital circuit are driven by state nodes. This is because a flipflop output retains its value until a clock pulse is applied to the flop. Structurally, a state node can be any node on a combinatorial feedback loop in a circuit.